Hi all,
Our next virtual meeting will be at 12pm (EST) Wednesday, February 24,
where James Robins presents research on "Estimation of Optimal Testing and
Treatment Regimes under No Direct Effect (NDE) of Testing."
*Abstract*:
In this talk I describe new, highly efficient estimators of optimal joint
testing and treatment regimes under the no direct effect assumption that a
given laboratory, diagnostic, or screening test has no effect on a
patient's clinical outcomes, except through the effect of the test results
on the choice of treatment. The proposed estimators attain high efficiency
because they leverage this "no direct effect of testing" (abbreviated as
NDE) assumption.
What is surprising and, indeed, unprecedented in my experience, is that, in
a substantive study of HIV infected subjects, our new estimators delivered
a 50-fold increase in efficiency (and, thus, a 50 fold reduction in
required sample size) compared to estimators that fail to leverage the NDE
assumption! In this talk I review the results of this HIV study, describe
the new estimators, and provide guidance as to when such large gains in
efficiency are to be expected.
Areas in which our new, more efficient estimators should be particularly
important is that of cost-benefit analyses wherein the costs of diagnostic
tests (such as MRIs to screen for lung cancer, mammograms to screen for
breast cancer, and urinary cytology to screen for bladder cancer) are
weighed against the clinical value of the information supplied by the test
results. In a political science context, candidates often conduct private
polls and focus groups to help update campaign outreach decisions such as
the number and content of social media and television ad buys to be
allocated to various demographic groups. One can view private polls and
focus groups as tests and outreach decisions as treatments that together
satisfy no direct effect of testing on the outcome of the election except
through the test results on the choice of treatment.
*Message to the audience*:
The speaker Jamie Robins suggests you read the following less technical
sections of the paper
<https://projects.iq.harvard.edu/files/applied.stats.workshop-gov3009/files/efficient_estimation_of_optimal_regimes_under_a_no_direct_effect_assumption.pdf>
that
cover many of the main ideas.
Section 1: Introduction
Section 4: The NDE of Testing Assumption
Section 5.1
Section 7
Section 8 and 8.1 stopping after remark 7
*Link to the paper*: URL
<https://projects.iq.harvard.edu/files/applied.stats.workshop-gov3009/files/efficient_estimation_of_optimal_regimes_under_a_no_direct_effect_assumption.pdf>
*Zoom link*:
https://harvard.zoom.us/j/97787602526?pwd=Uzh3bVVVS0F4TEVYQTJlV3BQNjcydz09
*Schedule of the workshop*:
https://projects.iq.harvard.edu/applied.stats.workshop-gov3009
Looking forward to seeing you all on Wednesday!
Best,
Soichiro
--
Soichiro Yamauchi
PhD candidate
Harvard University
URL:
https://soichiroy.github.io/